i have not found a better motor yet what i did find was my evaporater clogged with 20 plus years of crap i removed the blower motor and the resistor and used a garden hose from both side and flushed 90 percent out of it ,i got much better air flo from my vents it will hit back seat passemgers now . Still will be searching for bolt in upgrade though

 

Purchased a wider blower motor cage for a 1987 blazer going to try and install today.Results to be posted later. Four Seasons Blower Wheel 35601

 

New wheel was a direct replacement. Just had to sand surface rust of motor shaft so new wheel bottoms out before allen set screw it tightened. Id say on high speed Im getting about 25% more flow from vents. Not bad results for a 13.00 investment.

 

So the shaft size and mounting are identical?
Do u think the weight of the blazer unit is much higher due to it being metal?

 

Dont think theres much if any its aluminum. And balanced. It would be grams if you were to weigh it. Its slightly smaller in circumference bot wider in length by about 1/2 in. yes shaft are exact size ....0.94 compaired to 0.44 in weight.Just checked.

 

I got mine of ebay but auto zone list it. My next upgrades gonna be a resistor that allows more voltage on high setting.Motor blew like crazy when connected to battery....http://www.autozone.com/cooling-heat...5_0_7730_5281/

 

He's gonna do a complete write-up for us.

 

On a resistor yes blower motor wheels pretty straight forward.

 

Question why would blower blow faster hooked directly to battery than thru resistor since its also straight connection? Voltage drop that much thru harness...

 

This is not where I wanna go with a resistor upgrade. Im more into plug and play upgrade for the average guy to do.,....http://www.jeepforum.com/forum/f11/d...re-fix-580627/

 

I would suggest you do some reading on what a resistor does.

A resistor converts electrical energy into heat, dropping voltage across it's terminals.

When you connect the blower motor to the battery directly, as it is in the high setting, the blower motor has 12V.

When you connect a resistor in series between the blower motor and battery, the blower motor might only see say 10V or 8V. This is how the blower motor resistor pack functions, a variety of resistors to allow for different blower speeds selected by the driver.

 

Ks. Wouldn't the high switch setting not resist current at all,& be sending the full 12 volts to the motor?

 

In theory yes, but there will still be resistance/voltage loss in the wiring, switch, connectors, etc. so even on "high" it won't see as much voltage as a direct connection to the battery. It is the same reason you get a major increase in headlight brightness with an aftermarket relay harness, the factory wiring on the XJ was the bare minimum and allows for significant voltage drop.

 

Exactly ^^

Side note: A lot of electrical issues are caused by an old blower motor drawing excess current due to worn bearings/windings/contacts which in turn melts connectors and wipes out the resistor packs. Simple fix is to replace the blower motor.

 

points to kstopps post..
yep, thats exactly what happened to me.
replaced the blower motor and resister.. plastic stuff stopped melting